JP4338023B2 - Isothiocyanate-based underwater biofouling inhibitor and biofouling prevention coating - Google Patents

Description

  The present invention relates to an underwater organism adhesion preventive agent and an underwater organism adhesion prevention coating material for preventing harmful aquatic organisms such as shellfish from adhering. In particular, underwater organisms should adhere to equipment placed in seawater such as ship bottoms, fishing nets, buoys, thermal power or nuclear power plants and cooling water intakes, marine structures, underwater structures or reservoirs of various industries. The present invention relates to an underwater bio-adhesion inhibitor and an underwater bio-adhesion paint used for preventing water.

  Ship bottoms, equipment placed in seawater such as buoys and oil fences, aquaculture or stationary fishing nets, marine structures such as piers and sluices, condenser cooling water systems for thermal or nuclear power plants, heat exchanger cooling in the chemical industry Aquatic animals such as mussels, barnacles, oysters, hydroworms, hydra, serpra, squirts, bryophytes, snails, etc., in areas that are constantly in contact with seawater or fresh water, such as water intakes, underwater structures such as dam accessories, and reservoirs Algae such as Aosa, Aonori and Shiomidomi adhere and propagate.

  The adhesion of these aquatic organisms to the ship causes an increase in fluid resistance, resulting in a decrease in navigation speed, an increase in fuel consumption, and a loss such as the cost of cleaning the bottom of the ship. Moreover, when these aquatic organisms adhere to the aquaculture net, the circulation of seawater decreases, leading to the growth inhibition of the cultured fish and the frequent occurrence of fish diseases.

The attachment of aquatic organisms to offshore facilities, oceans and underwater structures can result in increased weight, significant operational inconvenience, and loss of aesthetics. Adhesion to the intake channel causes a decrease in the amount of water intake due to blockage of the intake channel, and further causes problems such as a decrease in thermal conductivity. Conventionally, in order to prevent the adhesion and propagation of these seawater and freshwater aquatic organisms, aquatic organism adhesion prevention coatings containing organotin compounds or cuprous oxide have been used.
The inventors of the present invention have previously found that the monoterpene derivative thiocyanate exhibits an excellent preventive effect against the adhesion of underwater organisms, and filed as Japanese Patent Application No. 2002-47100.
Japanese Patent Application No. 2002-47100

  In recent years, there are concerns about water pollution of the ocean, rivers, etc. due to heavy metals and harmful compounds, and adverse effects on human bodies due to contaminants. From this point of view, there are many substances that are subject to regulation with respect to the underwater organism adhesion inhibitor, and particularly, organotin compounds are strictly regulated. An object of the present invention is to provide a safe and effective underwater biofouling preventive agent and an underwater biofouling preventive paint which do not contain heavy metals, in place of these conventional underwater biofouling preventive agents.

  As a result of intensive studies to develop a more effective and environmentally significant compound as an underwater organism adhesion inhibitor, the present inventors have found that monoterpene derivative isothiocyanate is effective in preventing organism adhesion in water. As a result, the present invention has been completed.

  That is, the present invention provides the formula (a)

(A)

(In the formula, n is an integer of 1 to 12, and R is

And an isothiocyanate ester of a monoterpene derivative represented by the formula (1).

  The present invention also relates to an underwater bioadhesion-preventing paint containing an isothiocyanate ester of a monoterpene derivative represented by the formula (a).

  The underwater organism adhesion preventive agent of the present invention, in particular the underwater organism adhesion prevention coating, has a high ability to prevent underwater organism adhesion. It is extremely useful for preventing biofouling. Moreover, the underwater organism adhesion inhibitor of the present invention has a low load on the marine environment.

  The underwater organism adhesion inhibitor of the present invention contains a compound represented by the formula (a) (an isothiocyanate ester of a monoterpene derivative) as an active ingredient. The number n of methylene groups in the compound represented by the formula (a) is an integer of 1 to 12, preferably 6 to 12. It is difficult to synthesize isothiocyanate having n of 13 or more.

  The compound represented by the formula (a) can be prepared by forming a methylene side chain on a monoterpene, then reacting with a thiocyanate to synthesize a thiocyanate, and then isomerizing it. For example, by reacting a hydroxyl group-containing monoterpene with a strong alkali to ionize the hydroxyl group of the hydroxyl group-containing monoterpene, 1, n-dihalogenoalkane can be reacted, and a methylene side chain can be formed. A thiocyanate ester of a monoterpene derivative can be prepared by reacting a monoterpene derivative formed by reacting a hydroxyl group-containing monoterpene with 1, n-dihalogenoalkane to form a methylene side chain and a thiocyanate. Further, the thiocyanate ester of this monoterpene derivative can be isomerized by heating at a high temperature to produce a compound represented by the formula (a).

  As the hydroxyl group-containing monoterpene, geraniol, β-citronellol, linalool, menthol, α-terpineol or borneol is used.

  By using geraniol as the hydroxyl group-containing monoterpene, the isothiocyanate ester represented by the formula (h) is used, the β-citronellol is used, the isothiocyanate ester represented by the formula (i) is used, and linalool is used. By using an isothiocyanate represented by the formula (j), menthol, an isothiocyanate represented by the formula (k), and α-terpineol, By using borneol as the isothiocyanate, the isothiocyanate represented by the formula (m) can be produced.

(H)
(I)
(J)
(K)
(L)
(M)

  Examples of 1, n-dihalogenoalkane include dibromoalkanes such as 1,2-dibromoethane, 1,3-dibromopropane, 1,6-dibromohexane, 1,10-dibromodecane, 1,12-dibromododecane, , Dichloroalkane such as 10-dichlorodecane. N in the 1, n-dihalogenoalkane represents an integer of 1 to 12, and corresponds to the number of carbon atoms of the alkylene group, that is, the number of methylene groups of the resulting isothiocyanate.

Examples of the strong alkali include alkali metals such as sodium and potassium, alkaline earth metals such as calcium, alkali metal hydroxides such as sodium hydroxide, and basic metal oxides such as silver oxide.

Examples of the thiocyanate include alkali metal salts such as potassium thiocyanate, sodium thiocyanate, and lithium thiocyanate.

When ionizing a hydroxyl group-containing monoterpene, a reaction solvent may not be used, and a reaction solvent can also be used. As the reaction solvent, ethers such as diethyl ether and tetrahydrofuran can be used. The reaction temperature can be not lower than the boiling point of the solvent, usually 0-100 ° C, more preferably 10-75 ° C. If it is less than 0 ° C, the hydroxyl group-containing monoterpene is less likely to be ionized, and if it exceeds 100 ° C, side reactions tend to occur.

For the reaction in which 1, n-dihalogenoalkane is added to ionized hydroxyl group-containing monoterpene to introduce a methylene side chain, alcohol such as methanol or ethanol can be used as a solvent. The reaction temperature is not higher than the boiling point of the solvent, usually 0-100 ° C, more preferably 20-80 ° C. This is because the reaction between the ionized hydroxyl group-containing monoterpene and the 1, n-dihalogenoalkane is less likely to occur when the temperature is less than 0 ° C, and side reactions are likely to occur when the temperature exceeds 100 ° C. The boiling point of methanol and ethanol used as the reaction solvent is preferably set as the reaction temperature.

The reaction of a monoterpene derivative in which a 1, n-dihalogenoalkane is allowed to act on a hydroxyl group-containing monoterpene to form a methylene side chain and thiocyanate can be carried out by using a reaction solvent. As the reaction solvent, ketones such as acetone and amides such as N, N-dimethylformamide can be used. The reaction temperature can be not higher than the boiling point of the solvent, usually preferably −60 to 180 ° C., more preferably 20 to 80 ° C. Below -60 ° C, the reaction between the monoterpene derivative having a methylene side chain and thiocyanate hardly occurs, and when it exceeds 180 ° C, side reactions tend to occur. As the reaction solvent, when acetone is used, it is preferable that the boiling point of acetone be the reaction temperature.
The isomerization of the thiocyanate ester of the monoterpene derivative can be performed by using a reaction solvent. As the reaction solvent, amides such as N, N-dimethylformamide can be used. The reaction temperature is usually preferably 30 to 80 ° C, more preferably 50 to 120 ° C. If it is less than 30 ° C, isomerization hardly occurs, and if it exceeds 180 ° C, side reactions tend to occur.

The obtained compound represented by the formula (a) can be purified using column chromatography, thin layer chromatography or the like.

The underwater organism adhesion inhibitor of the present invention contains one or more compounds represented by the formula (a). The underwater organism adhesion inhibitor of the present invention can contain 0.001 to 50% by weight of the compound represented by the formula (a). When the amount is small, there is a tendency that the effect is small and the contamination with attached organisms is likely to occur. The content is preferably 1 to 10% by weight.

The underwater organism adhesion inhibitor of the present invention may contain other components other than the compound represented by the formula (a). The underwater organism adhesion inhibitor of the present invention can contain a compound that acts as an active ingredient of the underwater organism adhesion inhibitor as another component. Examples of the compound that acts as an active ingredient of the underwater organism adhesion inhibitor other than the compound represented by the formula (a) include inorganic compounds such as cuprous oxide, copper powder, cuprous thiocyanate, copper sulfate, zinc sulfate, nickel sulfate and the like. Organic copper compounds such as oxine copper, copper acetate, copper naphthenate and copper pyrithione; organic nickel compounds such as nickel acetate and nickel dimethyldithiocarbamate; organic such as zinc acetate, zinc carbamate, zinc dimethyldithiocarbamate and zinc pyrithione N-trihalomethylthiophthalimide such as zinc compounds, N-trichloromethylthiophthalimide, N-fluorodichloromethylthiophthalimide; bis (dimethylthiocarbamoyl) disulfide, ammonium N-methyldithiocarbamate, ethylenebis (dithiocarbamic acid) ammonium Dithiocarbamic acids such as um; N-arylmaleimides such as N- (2,4,6-trichlorophenyl) maleimide, N-4-tolylmaleimide, n-3-chlorophenylmaleimide; 3-benzylideneamino-1,3-thiazolidine -3-substituted amino-1,3-thiazolidine-2,4-diones such as 2,4-dione and 3- (4-methylbenzylideneamino) -1,3-thiazolidine-2,4-dione; dithiocyanomethane, dithiocyano Dithiocyano compounds such as ethane and 2,5-dithiocyanothiophene; thylazine compounds such as 2-methylthio-4-t-butylamino-6-cyclopropylamino-S-triazine; 2,4,5,6-tetrachloroisophthalo Nitrile, N, N-dimethyl N′-dichlorophenylurea, 4, 5 Dichloro-2-n-octyl-isothiazolin-3-one, N, N-dimethyl-N′-phenyl- (N-fluorodichloromethylthio) sulfamide, tetramethylthiuram disulfide, 3-iodo-2-propynylbutylcarbamate, 2- ( Methoxycarbonylamino) benzimidazole, 2,3,5,6-tetrachloro-4- (methylsulfonyl) pyridine, diiodomethylparatolylsulfone, phenyl (bispyridine) bismuth dichloride, 2- (4-thiazolyl) benzimidazole, pyridine chile Phenylborane or the like can be used.

The underwater organism adhesion inhibitor of the present invention can be prepared in various forms such as a paint form (underwater organism adhesion prevention paint), a solution form, and an emulsion form. The underwater organism adhesion inhibitor of the present invention can contain various other components depending on its form. Preparation of the underwater organism adhesion inhibitor of each form can be performed by the general formulation normally performed.

For example, the underwater organism adhesion preventing paint of the present invention can be obtained by incorporating a compound represented by the formula (a) into the paint. The underwater organism adhesion-preventing paint of the present invention can contain a film-forming component, a pigment, an additive, a solvent, and the like as components other than the compound represented by the formula (a).

Examples of the film forming component include oils such as linseed oil, natural resins such as rosin, and synthetic resins such as vinyl chloride. As pigments, coloring pigments such as titanium white, zinc white, bengara, rust preventive pigments such as zinc dust and red lead, extender pigments such as calcium carbonate, clay, talc, barium sulfate, aluminum paste, cuprous oxide, glass beads, Special functional pigments such as mica can be mentioned. Examples of the additive include alkylamine, dibutyl phthalate, diethyl phthalate, aluminum stearate, bentonite, methyl cellulose, silicone, surfactant, and metal naphthenate soap. Examples of the solvent include petroleum mixed solvents, mineral spirits, toluene, xylene, ethanol, butanol, isopropanol, cellosolve, ketones, esters, water, and the like.

The underwater organism adhesion preventing coating of the present invention can contain 0.001 to 50% by weight of the compound represented by the formula (a). When the amount is small, there is a tendency that the effect is small and the contamination with attached organisms is likely to occur. The content is preferably 1 to 10% by weight.

The underwater bioadhesion inhibitor prepared in the form of the solution of the present invention can be prepared, for example, by blending the compound represented by the formula (a) with a film forming agent. As the film forming agent, for example, xylene, toluene, methyl ethyl ketone, methanol and the like can be used. The underwater bioadhesion inhibitor prepared in the form of a solution can contain 0.001 to 50% by weight of the compound represented by the formula (a). When the amount is small, there is a tendency that the effect is small and the contamination with attached organisms is likely to occur. The content is preferably 1 to 10% by weight.

The underwater bioadhesion inhibitor prepared in the form of the emulsion of the present invention can be prepared by a conventional method in which the compound represented by the formula (a) is dissolved in a solvent and a surfactant is added. As the solvent, xylene, toluene, methyl ethyl ketone, methanol and the like can be used. As the surfactant, nonionic, anionic, cationic and amphoteric ones can be used as appropriate. For example, ethylene oxide and / or propylene oxide polymerized with alkylphenol, higher alcohol, alkylnaphthol, higher fatty acid, fatty acid ester, dialkyl phosphate amine, etc .; alkyl sulfate ester salt such as sodium laurate; 2-ethylhexene Alkyl sulfonates such as sodium sulfonate; aryl sulfonates such as sodium dodecylbenzene sulfonate and the like can be used.

The underwater bioadhesion inhibitor prepared in the form of an emulsion is preferably 0.001 to 50% by weight of the compound represented by the formula (a). More preferably, it can contain 0.01 to 10 weight%. If it is less than 0.01% by weight, it tends to be easily contaminated by the attached organism, and if it exceeds 10% by weight, the effect on the attached organism tends not to increase so much.

The underwater organism adhesion preventive agent of the present invention includes equipment placed in seawater such as ship bottoms, fishing nets, buoys, thermal power or nuclear power plants, and water intakes for cooling water of various industries, offshore structures, underwater structures or reservoirs, etc. It is possible to prevent harmful harmful aquatic organisms such as shellfish from adhering.

By applying the underwater organism adhesion-preventing paint of the present invention to an application target that needs to prevent the adhesion of underwater organisms to form a coating film, it is possible to prevent adhesion of the underwater organism to the application target.

The underwater organism adhesion inhibitor prepared in the form of the solution or emulsion of the present invention is applied to an application object that needs to prevent adhesion of underwater organisms, in particular, aquatic fish nets, stationary fish nets, etc. Can be prevented.

Hereinafter, although an example and a comparative example explain the present invention, the range of the present invention is not limited to this.

Example 1
<Production of isothiocyanate ester of monoterpene derivative>
A three-necked flask equipped with a condenser, a thermometer and a stirrer was charged with 88 ml of geraniol and 50 ml of diethyl ether, and 10 g of finely cut sodium was added thereto. After adding 2 g of potassium iodide, 100 ml of 1,10-dibromodecane was added dropwise over about 1 hour, and then 300 ml of ethanol was added dropwise over about 3 hours, followed by reaction under reflux conditions for 10 hours. It was. The reaction product was extracted with ether and then purified by column chromatography to obtain 60 g of an intermediate (monoterpene derivative) (1).

A similar apparatus was charged with 50 g of intermediate (1), 15 g of potassium thiocyanate and 200 ml of N, N-dimethylformamide and reacted at 80 ° C. for 25 hours. The reaction product was extracted with ether and then purified by column chromatography to obtain 39 g of a thiocyanate ester (1) of a monoterpene derivative.
A similar apparatus was charged with 39 g of a monoterpene derivative thiocyanate (1) and 200 ml of N, N-dimethylformamide, and reacted at 100 ° C. for 25 hours. The reaction product was extracted with ether and then purified by column chromatography to obtain 26 g of a monoterpene derivative isothiocyanate (1).

<Manufacture of underwater organism adhesion prevention paint>
Using the isothiocyanate ester (1), the underwater biological adhesion preventive coating material of the present invention was prepared at the blending ratio shown in Table 2.

<Evaluation of underwater organism adhesion prevention performance>
The test plate was prepared by brush-applying the underwater organism adhesion preventing paint on both sides of an FRP (glass fiber reinforced polyester) plate (150 × 300 mm) so that the dry film thickness was 70 μm. This test plate was immersed in a 1.0m-deep sea from a test cage installed off Sakagoe, Ako City, Hyogo Prefecture, and the state of organism adhesion on the test plate surface was periodically investigated. The survey results after 4 months and 6 months are shown in Table 3. As a control, the results when no underwater organism adhesion preventing paint was used are shown.

In addition, the evaluation of the underwater organism adhesion prevention performance was carried out by visual observation, and the coverage by adhesion organisms on the coating film area was evaluated in six stages. It shows that a coverage is so small that a number is large. That is, in Table 3, “5” indicates that no fouling organisms adhered, “4” indicates that fouling organism adhesion (coverage) was 5% or less, and “3” was 6 to 10%. "2" was 11 to 25%, "1" was 26 to 50%, and "0" was 51% or more.

Examples 2-9
In the same apparatus as in Example 1, 50 ml of each monoterpene (A) and diethyl ether shown in Table 1 were charged, and 10 g of finely cut sodium was added thereto. After adding 2 g of potassium iodide, a predetermined amount of each dibromoalkane (B) shown in Table 1 was added dropwise over about 1 hour, and then 300 ml of ethanol was added dropwise over about 3 hours under reflux conditions. For 10 hours. The reaction product was extracted with ether and then purified by column chromatography to obtain intermediates (monoterpene derivatives) (2) to (9). The yield of each obtained intermediate is shown in Table 1.

In a similar apparatus, 50 g of intermediates (2) to (9), potassium thiocyanate (C) in an amount shown in Table 1, and 200 ml of N, N-dimethylformamide were charged and reacted at 80 ° C. for 25 hours. The reaction product was extracted with ether and then purified by column chromatography to obtain monoterpene derivative thiocyanate esters (2) to (9). Table 1 shows the yields of the obtained thiocyanate esters (2) to (9) of the monoterpene derivative.
In the same apparatus, the amounts shown in Table 1 of thiocyanate esters (2) to (9) of monoterpene derivatives and 200 ml of N, N-dimethylformamide were charged and reacted at 100 ° C. for 25 hours. The reaction product was extracted with ether and purified by column chromatography to obtain isothiocyanate esters (2) to (9) of monoterpene derivatives. Table 1 shows the yield of the obtained monoterpene derivative isothiocyanate esters (2) to (9).

Subsequently, using the obtained isothiocyanate esters (2) to (9), the underwater organism adhesion preventing paint of the present invention was prepared according to the blending ratio shown in Table 2, and the underwater organism adhesion preventing performance was obtained in the same manner as in Example 1. Evaluation was performed. The results are shown in Table 3.

Comparative Example 1
A paint was prepared at a blending ratio shown in Table 2 using cuprous oxide instead of the isothiocyanate ester in Example 1, and the underwater organism adhesion disaster prevention performance was evaluated in the same manner as in Example 1.
The results are shown in Table 3.

Comparative Example 2
A paint was prepared using a commercially available underwater organism adhesion inhibitor (pyridine triphenylborane) at a blending ratio shown in Table 2, and the underwater organism adhesion prevention performance was evaluated in the same manner as in Example 1.
The results are shown in Table 3.

Example 10
In the same apparatus as in Example 1, 88 ml of geraniol and 50 ml of diethyl ether were charged, and 10 g of finely cut sodium was added thereto. After adding 2 g of potassium iodide, 50 ml of 1,2-dibromoethane was added dropwise over about 1 hour, and then 300 ml of ethanol was added dropwise over about 3 hours and reacted under reflux conditions for 10 hours. It was. The reaction product was extracted with ether and purified by column chromatography to obtain 53 g of an intermediate (monoterpene derivative) (10).

In a similar apparatus, 50 g of the intermediate (10), 20 g of potassium thiocyanate and 200 ml of N, N-dimethylformamide were charged and reacted at 80 ° C. for 25 hours. The reaction product was extracted with ether and then purified by column chromatography to obtain 41 g of a thiocyanate ester (10) of a monoterpene derivative.
In a similar apparatus, 41 g of a monoterpene derivative thiocyanate (10) and 200 ml of N, N-dimethylformamide were charged and reacted at 100 ° C. for 25 hours. The reaction product was extracted with ether and purified by column chromatography to obtain 20 g of a monoterpene derivative isothiocyanate (10).

Next, using the obtained isothiocyanate ester (10), the underwater organism adhesion preventing paint of the present invention was prepared according to the blending ratio shown in Table 2, and the underwater organism adhesion preventing performance was evaluated in the same manner as in Example 1. It was. The results of the performance evaluation were “3” after 4 months and “2” after 6 months.

  As is apparent from the results shown in Table 3, the underwater bioadhesion-preventing paints (Examples 1 to 9) using the isothiocyanate esters (1) to (9) were equivalent to or better than the paints of Comparative Examples 1 and 2. It was confirmed to have a high ability to prevent the adhesion of underwater organisms. The performance of the paint prepared in Example 9 was almost the same as that of Comparative Example 1 using cuprous oxide, but the cuprous oxide used in Comparative Example 1 was a heavy metal compound, and the effluent was a marine environment. It is considered to have an adverse effect on

Claims (2)

Formula (a);
(A)
Wherein n is an integer from 1 to 12, and R is
And an isothiocyanate ester of a monoterpene derivative represented by (1). A paint using the underwater organism adhesion inhibitor according to claim 1.